(8) WP (write protect pin) Setting the WP pin to Vcc (HIGH level) has the same eect as using the write protect command, and inhibits writing of data to addresses 80 to FFh, among the 256 word address data. Normal writing is enabled by set- ting this pin to GND (LOW level). (If the write protect command is used to inhibit writing, data cannot be writ- ten regardless of the status of the WP pin.) The WP pin is equipped with an internal pull-down resistor, so if the protect function is not being used, this should be left open or set to GND.